Diners at Lussmanns know the fish they eat is caught in UK waters, the meat is free range and if they can't finish what's on the plate, they can take the leftovers home in a 100% recycled and biodegradable doggy box.

This family fish and grill business with restaurants in St Albans and Hertford has increased turnover by 12% and has fed 100,000 diners in the past year. Despite the recession, it's now planning to open a third branch.

Lussmanns has a mission to make a minimal impact on the environment. All its fish is sustainable and it is in the process of obtaining a Marine Stewardship Council certificate.

The chicken, beef and pork it uses is free range and high-welfare, charcuterie is welfare-driven and outdoor bred and, increasingly, its suppliers are more sustainable. Lussmanns buys tea from Cornwall, water is 100% carbon neutral and the addition of more British craft beers are steadily ensuring a UK-only list.

The company has adapted menus so food on offer is more seasonal. Animal welfare is always taken into account the company makes the most of meat carcasses. It visits suppliers to ensure they meet its standards, visits food shows to find new suppliers and seeks advice from the Sustainable Restaurant Association (SRA).

Food used in the restaurant arrives in reusable crates, all customers are offered tap water and doggy boxes, three quarters of waste is recycled and food leftovers are composted for the National Grid. What's more, Lussmanns tells customers exactly what it's doing for the environment.

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